The pancreas is a gland located deep in the abdomen between the stomach and the spine. The pancreas performs exocrine and endocrine functions. Its exocrine functions include secreting pancreatic juice containing digestive enzymes into the digestive tract. Its endocrine functions include producing hormones such as insulin glucagon, and somatostatin, for controlled release into the bloodstream.
The sphincter of Oddi is a muscular structure that encompasses the confluence of the distal common bile duct and the pancreatic duct of the pancreas as they penetrate the wall of the duodenum. The term “sphincter of Oddi dysfunction” describes a clinical syndrome of biliary or pancreatic obstruction related to mechanical or functional abnormalities of the sphincter of Oddi. The sphincter of Oddi is composed of small circular and longitudinal muscular segments that are approximately six to ten millimeters in total length and are contained mostly within the wall of the duodenum. The muscle fibers surround the intraduodenal segment of the common bile duct and the ampulla of Vater.
Sphincter of Oddi dysfunction has been hypothesized as a cause of idiopathic recurrent pancreatitis and pancreatitis occurring after endoscopic retrograde cholangiopancreatography (ERCP). To illustrate, sphincter of Oddi dysfunction may lead to a build-up of pancreatic juices within the pancreatic and bile ducts, thereby causing ductal distension, tissue damage, and pain. Due to the increased pressure in the duct, the fluid may seek alternate, unnatural routes for release, which may lead to the development of fissures in the pancreas. These fissures may leak pancreatic enzymes that digest surrounding tissues and organs and thereby cause severe abdominal pain and organ damage.